1. Field of the Invention
The present invention relates to a speaker supporting device suitable for use in various types of electronic devices having built-in speakers, such as mobile telephones, PHS (personal handyphone systems), other information mobile terminals and the like, and an electronic device comprising this speaker supporting device, and more particularly relates to a speaker supporting structure and assembly structure of an electronic device.
2. Description of the Related Art
Besides a speaker as a receiver that is used to reproduce communications sound, a speaker that is used to reproduce calling sounds and the like is disposed in a mobile telephone. These speakers are reduced in size and weight, and are mounted on wiring boards or on case internal members together with other electronic parts and disposed in the vicinity of respective sound emission holes in the rear side case and front surface side case.
Prior patent references relating to such speaker supporting structures include Japanese Patent Application Laid-Open No. 2002-10387 and Japanese Patent Application Laid-Open No. 2001-127862.
In FIG. 5 and the description of this figure in Japanese Patent Application Laid-Open No. 2002-10387, a structure in which a board on which electronic parts and the like functioning as control parts used to control the driving of the speaker is disposed between a shielding case and an LCD holder, and the speaker is fastened between the shielding case and a rear case while ensuring a front air chamber as a result of the shielding case being pressed by the board and an annular cushion disposed on the outer circumferential part of the speaker being compressed due to the screw fastening of the front case and rear case, is disclosed as a speaker device for mobile telephones and the like.
Furthermore, in Japanese Patent Application Laid-Open No. 2001-127862, a structure in which the speaker is held by a speaker holding member supported on a shielding case which is installed so that this shielding case straddles a printed board is disclosed as a speaker structure which facilitates the fastening and electrical wiring of the speaker.
Speakers that are mounted in mobile telephones are compact speakers with a diameter of approximately 15 mm, and do not have a structure in which the speaker itself is screw-fastened. Instead, as is disclosed in the above-mentioned patent references and the like, a simple supporting structure in which the speaker is sandwiched between other members, or in which the speaker is fastened to a specified member by means of an adhesive tape or the like, is employed.
Seen from the standpoint of the speaker alone, such supporting structures are extremely simple structures. However, in electronic devices such as mobile telephones or the like in which the mounting density of electronic parts is high and the speaker must be installed in a constricted space, the attachment of the speaker causes a deterioration in the assembly characteristics of such electronic devices such as mobile telephones or the like. Such a problem is not disclosed in the above-mentioned patent references, and cannot be solved by the techniques disclosed in these patent references.